From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F3D1C6FD1F for ; Wed, 22 Mar 2023 20:11:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232129AbjCVULm (ORCPT ); Wed, 22 Mar 2023 16:11:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50982 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232024AbjCVUKz (ORCPT ); Wed, 22 Mar 2023 16:10:55 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 58D956B310; Wed, 22 Mar 2023 13:03:49 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id AB4BC622C0; Wed, 22 Mar 2023 20:02:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 61500C433EF; Wed, 22 Mar 2023 20:02:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679515365; bh=RuYnVTJwWCkgS5pZsTRyfgbm1jPX/9A6YF9I++YlZ7Y=; h=From:To:Cc:Subject:Date:From; b=cBiSET3Fpf+y2+2BG/5QIGlDsq6wXl1gjfmAEIQR1bSS5NuH93cFUyyRlGrovxalV mynPoJlajZReORER+DaY9sLMzM+4uorwzSRoDrKceUJKuqZEuhiXPghe9IDVLV/mJw KfqTHGZnFWm/kGai3e1iAItLRj0dJypWY4qRX+t/Xl8ayKe565xj8jssCoYTzfgId9 h7Sus9FvHUPsJEMtyFGWbgjLGYh7ZoDrkc0m+eWfevPFkSd/mhq7YRtBDUuC8AiJER reO5Bx31DfNshJVY9SZAZfgsKm5HdscdJDWLYxbwIPGt08bdu0iv2zu13fIK5MXgUh a0wHuyzX7Bczw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: NeilBrown , Dan Carpenter , Song Liu , Sasha Levin , linux-raid@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 1/9] md: avoid signed overflow in slot_store() Date: Wed, 22 Mar 2023 16:02:33 -0400 Message-Id: <20230322200242.1997527-1-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org From: NeilBrown [ Upstream commit 3bc57292278a0b6ac4656cad94c14f2453344b57 ] slot_store() uses kstrtouint() to get a slot number, but stores the result in an "int" variable (by casting a pointer). This can result in a negative slot number if the unsigned int value is very large. A negative number means that the slot is empty, but setting a negative slot number this way will not remove the device from the array. I don't think this is a serious problem, but it could cause confusion and it is best to fix it. Reported-by: Dan Carpenter Signed-off-by: NeilBrown Signed-off-by: Song Liu Signed-off-by: Sasha Levin --- drivers/md/md.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/md/md.c b/drivers/md/md.c index aa2993d5d5d38..64558991ce0a0 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -3082,6 +3082,9 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len) err = kstrtouint(buf, 10, (unsigned int *)&slot); if (err < 0) return err; + if (slot < 0) + /* overflow */ + return -ENOSPC; } if (rdev->mddev->pers && slot == -1) { /* Setting 'slot' on an active array requires also -- 2.39.2